Indirect Nutrition and Mobility Risks during Hospitalization: An Architectural Perspective on the nutritionDay Study Findings

Nutrition and mobility risks include complex and interrelated physiological, medical, and social factors. A growing body of evidence demonstrates that the built environment can affect patients’ well-being and recovery. Nevertheless, the relationship between the built environment, nutrition, and mobility in general hospitals is largely unexplored. This study examines the implications of the nutritionDay study’s results for the architectural design of hospital wards and nutrition environments. This one-day annual cross-sectional study uses online questionnaires in 31 different languages to collect ward-specific and patient-specific variables. The main findings relevant to the design of hospital wards were: (1) 61.5% of patients (n = 48,700) could walk before hospitalization and (2) this number dropped to 56.8% on nutritionDay (p < 0.0001), while the number of bedridden patients increased from 6.5% to 11.5% (p < 0.0001), (3) patients who needed more assistance had a much longer mean LOS than mobile patients, (4) mobility was associated with changes in eating, and (5) 72% of units (n = 2793) offered additional meals or snacks, but only 30% promoted a positive eating environment. The built environment may indirectly affect hospitalized patients’ mobility, independence, and nutritional intake. Possible future study directions are suggested to further investigate this relationship.


Introduction
Hospital wards, used for patient recovery, rehabilitation, therapy, and monitoring, are among the hospital's main functional departments and employ a wide range of personnel [1]. Patients spend the majority of their hospital stay in the wards, and the wards have more floor space than any other hospital department [2]. How a hospital and the individual wards are organized in terms of layout structure, size of spaces, and their connections can greatly affect the behavior and well-being of patients and staff members. Being an inpatient is unpleasant and distressing; patients in a ward environment are likely to be weak, anxious, and have limited control over their environment [3]. Furthermore, malnutrition and decreased mobility are some of the most prevalent issues in hospitalized patients [4], leading to adverse outcomes such as functional decline, a longer hospital stay, the increased necessity for nursing home placement following discharge, and increased mortality risk [5][6][7][8][9]. However, all of the aspects negatively affecting patients' nutritional intake and mobility during hospitalization are still unclear.
Malnutrition is a common and complex condition that affects many people in an acute hospital setting [10]. To a great extent, malnutrition is caused by either an increase in the

Research Method
The nutritionDay (www.nutritionday.org, accessed on 15 February 2023) is a global initiative created to increase understanding and awareness of malnutrition in healthcare facilities. It is a one-day annual cross-sectional study repeated yearly since 2006 in hospitals worldwide. Online questionnaires in 31 different languages are used to collect ward-specific and patient-specific variables [37]. Questionnaires are designed to enable the participation of any interested ward; no specialized knowledge or specific laboratory measurements are necessary. Participation after online registration is free of charge. All participating units can download a unit-specific report for auditing purposes compared to units with a similar medical specialty.
The first questionnaire addresses the structure, human resources, and standard nutrition procedures of the ward in which the patient resides and is to be completed with the help of the head nurse or physician. The second questionnaire addresses the caregiver's view of the patient, including data on the patient's age, height, weight, medical or surgical condition, comorbidities, and type of nutritional support given. The third questionnaire allows patients to self-report their actual food intake, their self-rated health status, including their mobility level before hospitalization, and their actual mobility status. Patients received help to fill out the questionnaire when needed.

Sample and Data Analysis
Because of the new inclusion of "mobility before admission" in questionnaires, the 2016-2021 nutritionDay database containing data from 49,444 patients was used for analysis. We included all 48,700 patients aged 18 years or above. Unit and patient data are reported as median with interquartile range {IQR} or proportions. Comparison between patient groups with different risk factors was performed with general linear models where the group without risk factors was used as a reference and units were considered as random factors. Association of risk factors with the length of stay before and after nutritionDay was also determined with general linear models with risk factors as categorical variables and units as random factors. All estimates are reported as mean with a 95% confidence interval. All analyses were performed with STATA 15.1.

Mobility, Nutritional Intake, and Well-Being
Mobility was limited for more than a quarter of patients already before hospital admission. When evaluated at nutritionDay, this proportion increased to one-third of patients, with the proportion of patients who were bedridden more than doubling (Table 3). During the period between hospital admission and nutritionDay, a larger proportion of patients indicated an improvement in strength (41.7%) than a decrease in strength (18.3%) ( Table 3). Mobility before admission was associated with actual mobility (Figure 1) since about three-fourths of patients who were mobile before admission were also mobile in the hospital and three-fourths of patients who were bedridden remained bedridden. Interestingly, 10% of the previously mobile patients needed help, and 4% were bedridden, whereas 26% of the patients previously needing a cane or help considered themselves mobile within the hospital environment. Between admission and nutritionDay, 12.2% of patients' mobility worsened ( Figure 1). Mobility before admission is also associated with self-perceived health. The proportion with "very good" or "good" self-rated health decreased from 52% to 25% with decreasing mobility and "poor" and "very poor" self-rated health increased from 12% to 40% ( Figure 2). Eating was not normal before hospitalization in one-third of patients, and not eating their full meal further increased to more than half of the patients. Accordingly, one-third indicated that their eating decreased, while only 14% indicated an increase (Table 4) since hospital admission. Decreased actual mobility was associated with decreased eating (Figure 3) of all the food served. Similarly, patients that became stronger also increased their food intake; it decreased in those feeling weaker compared with patients that did not change their food intake ( Figure 4). A large proportion of patients who reported feeling weaker (n = 8043) also had a decreased food intake (n = 5040) (63%). (Table 3). Mobility before admission was associated with actual mobility (Figure 1) since about three-fourths of patients who were mobile before admission were also mobile in the hospital and three-fourths of patients who were bedridden remained bedridden. Interestingly, 10% of the previously mobile patients needed help, and 4% were bedridden, whereas 26% of the patients previously needing a cane or help considered themselves mobile within the hospital environment. Between admission and nutritionDay, 12.2% of patients' mobility worsened ( Figure 1). Mobility before admission is also associated with self-perceived health. The proportion with "very good" or "good" self-rated health decreased from 52% to 25% with decreasing mobility and "poor" and "very poor" self-rated health increased from 12% to 40% ( Figure 2). Eating was not normal before hospitalization in one-third of patients, and not eating their full meal further increased to more than half of the patients. Accordingly, one-third indicated that their eating decreased, while only 14% indicated an increase (Table 4) since hospital admission. Decreased actual mobility was associated with decreased eating (Figure 3) of all the food served. Similarly, patients that became stronger also increased their food intake; it decreased in those feeling weaker compared with patients that did not change their food intake ( Figure 4). A large proportion of patients who reported feeling weaker (n = 8043) also had a decreased food intake (n = 5040) (63%).         Mobility before admission was strongly associated with length of stay between admission and nutritionDay as well as between nutritionDay and discharge ( Table 5). Reduced actual mobility and reduced actual eating were both associated with prolonged length of stay after nutritionDay ( Table 5). Length of stay after nutritionDay until discharge was more prolonged by impaired mobility by 1.7 (CI95 1.4-1.9) days for those needing help and 2.6 (CI95 2.3-2.9) days for those bedridden, corresponding to an increase of 33% and 50%, respectively. Reduced eating had a smaller effect of 0.35 (CI95 0.16-0.55) days for a half meal eaten and 0.94 (CI95 0.68-1.20) days for a quarter of meal eaten as well as in those eating nothing, 0.93 (CI95 0.55-1.30) days, despite being allowed to eat and was 0.96 (CI95 0.60-1.32) days after adjustment for length of stay before nutritionDay.  In the unit structure questionnaire, the medical staff was also asked to report on the strategies their unit implemented to support the nutritional intake of patients. The main strategies used in the participating units (n = 2793) were offering additional meals or snacks (2012, 72%), offering meal choices (1869, 67%), different portion sizes (1672, 60%), changing texture (2131, 76%), and considering patient problems with eating and drinking (2167, 78%) ( Figure 5). Only 828 units (30%) reported promoting a positive eating environment. Furthermore, it was not specified what exactly the term "positive eating environment" entailed. 6 *** {2-13} * significant difference in length of stay before or after nutritionDay between reference and individual risk factor categories (p < 0.01), *** (p < 0.0001) in GLM estimation.
In the unit structure questionnaire, the medical staff was also asked to report on the strategies their unit implemented to support the nutritional intake of patients. The main strategies used in the participating units (n = 2793) were offering additional meals or snacks (2012, 72%), offering meal choices (1869, 67%), different portion sizes (1672, 60%), changing texture (2131, 76%), and considering patient problems with eating and drinking (2167, 78%) ( Figure 5). Only 828 units (30%) reported promoting a positive eating environment. Furthermore, it was not specified what exactly the term "positive eating environment" entailed.

Main Findings and Their Implications
On nutritionDay, more than half of hospitalized patients reported that they could walk independently, one out of four patients needed assistance for mobility, and 11.5% were bedridden. Even though a large proportion of patients can walk independently, patients are consistently found to spend most of their day lying in bed, with a very low number of covered steps per day [28][29][30]. This creates significant issues, as even short periods of bed rest and low mobility can accelerate muscle loss during hospitalization [5,29,38]. Even the meals are served in bed-the majority of patients have meals at their bedside as the primary location [39,40]. On the other hand, the most successful supportive nutrition interventions in hospital settings, according to systematic reviews, are those that encourage social interaction and communal eating [25,41,42]. Only 45% of patients ate their whole meal on the nutritionDay and around a quarter of patients reported eating apart meals. It is common for family members to bring food in for patients [21]; we also found that 72% of units offered meals/snacks between main meals. These additional meals and snacks are usually eaten at the bedside as well. The patient's mobility level was also associated with the amount of lunch consumed. Only one-third of bedridden patients ate their complete lunch, and nearly 20% did not eat anything.
In our study, patients unable to walk independently had a much longer mean hospital stay than patients who could walk. Furthermore, 11.1% of patients were still hospitalized 30 days after the nutritionDay. This highlights that patients who need more assistance for mobility, eating, and other ADLs are staying much longer in the hospital, placing a significant burden on the nursing staff. Another important finding is that 18% of patients reported feeling weaker on the nutritionDay compared to admission. Changes in patients' mobility status during hospitalization are evident: the number of patients who could walk independently dropped from 61.5% before to 56.8% on nutritionDay. At the same time, the proportion of bedridden patients increased from 6.5% to 11.5%. This is not uncommon, as hospital-acquired disability has been observed in other studies [30,43]. Those above the age of 65 are at especially high risk: around a third experience functional deterioration (loss of independence in activities of daily living) after a hospital stay [44]. Older persons hospitalized for non-disabling diseases experience a functional decline both during hospitalization and in the month following discharge due to low mobility and decreased nutritional intake in the hospital [43].
These findings are relevant to the hospital design and, more specifically, ward design. Typical hospital wards often do not have a space where patients can eat outside their rooms, such as a shared dining room, as they are expected to eat at their bedside ( Figure 6-Type A). Even when dining rooms exist, they are often underutilized [27,39]. If the room is too far from the patient's room, it might be difficult for the patient to reach it independently. This creates more workload for the nursing staff to transport patients from their room to the dining room [45]. In a study in the stroke rehabilitation context, the distance was found to play a role in patients' mobility-patients were only independently visiting spaces close to their rooms [46]. Thus, if communal dining areas for hospitalized patients are implemented, they should be within a distance where most patients can reach them independently. In addition to transporting patients, another challenge of communal eating is keeping careful supervision over all patients during mealtimes, as some patients cannot eat outside their rooms [45]. This could be alleviated by positioning the dining room centrally on the ward and allowing for easy supervision via a large window close to the nurses' station [45]. This kind of schematic organization is shown in Figure 6 Type B. Another variation in ward layout design has the dining room at the end of the ward, sometimes shared with an adjacent ward ( Figure 6-Type C). Other concepts (such as small open seating/dining spaces in the corridors) exist, but they are rarely implemented in hospital design. It is unclear whether any of these options is the best possible solution for dining environments or if a different solution would be more beneficial for the patients. Because even a limited number of steps taken during hospitalization might mean the difference between functional decline and maintained independence [47], developing mobility-and nutrition-supporting environments may be a joint approach. Mealtimes also show potential to be used as a time to practice skills related to rehabilitation and recovery, such as improving mobility, dexterity, and psychological well-being [27,48]. Where patients eat is important, not only for the main meals of the day but also for snacks and food brought in by family between meals. Patients going independently to eat their meals in the communal dining room could be seen as a mobility exercise, and the dining room could be a place for socialization, which was already shown to improve nutritional intake [25,42]. The location of where main meals are eaten and where snacks are eaten might also not be in the same environment; there could be multiple communal dining options outside of patients' rooms to allow space to socialize with other patients or to be alone with their visitors. This multiple-space nutritional environment concept needs to be examined from the nurses' point of view as well, as it would increase the logistical challenges, such as transport and supervision [45].
The role of the built environment in increasing patients' mobility and activity was already investigated in specific groups, such as stroke patients and patients with dementia. These isolated research studies targeted particular patient groups, and it remains unclear how their findings could be transferred to the general hospital population. Thus, research investigating various environmental interventions to improve general hospital Because even a limited number of steps taken during hospitalization might mean the difference between functional decline and maintained independence [47], developing mobility-and nutrition-supporting environments may be a joint approach. Mealtimes also show potential to be used as a time to practice skills related to rehabilitation and recovery, such as improving mobility, dexterity, and psychological well-being [27,48]. Where patients eat is important, not only for the main meals of the day but also for snacks and food brought in by family between meals. Patients going independently to eat their meals in the communal dining room could be seen as a mobility exercise, and the dining room could be a place for socialization, which was already shown to improve nutritional intake [25,42]. The location of where main meals are eaten and where snacks are eaten might also not be in the same environment; there could be multiple communal dining options outside of patients' rooms to allow space to socialize with other patients or to be alone with their visitors. This multiple-space nutritional environment concept needs to be examined from the nurses' point of view as well, as it would increase the logistical challenges, such as transport and supervision [45].
The role of the built environment in increasing patients' mobility and activity was already investigated in specific groups, such as stroke patients and patients with dementia. These isolated research studies targeted particular patient groups, and it remains unclear how their findings could be transferred to the general hospital population. Thus, research investigating various environmental interventions to improve general hospital patient mobility is greatly lacking. Some spatial interventions on geriatric hospital units in the form of various environmental interventions [49,50] show the potential in activating patients and improving their mobility levels, but this is still insufficiently researched. Studies investigating the nutrition environment are more numerous but focus on particular elements in the environment, such as the presence of music [51][52][53], the presence of aquariums [54], the use of high-contrast plates and cutlery [55,56], or whether the meals were eaten in the dining room or at the bedside [22,27,57]. Several studies have found that patients/residents who dine in a communal setting benefit from greater nutritional intake, a lower risk of malnutrition, and enhanced socializing [22,58]. Most studies examining nutrition environments were conducted in dementia units in long-term care, not hospitals. Therefore, the hospital nutrition environment design to best support food intake is still an under-researched topic. The presented schematic layout organizations of the wards in Figure 6 are implemented differently in different hospitals around the world and their impact on patients' food intake and mobility has yet to be evaluated.
When designing hospital wards, our finding that the LOS of patients who are not independently mobile can stretch up to three weeks, on average, needs to be considered. For these patients, the built environment can greatly limit or support their everyday activities in the hospital. At the same time, communal dining can increase the burden on the nurses, who might prefer that all their patients eat in their rooms [45]. Nevertheless, mealtimes are an opportunity for patients to leave their beds and be physically active. If the wards were designed so patients could reach the communal dining environments independently, this would eliminate a significant workload for the nursing staff. Patients using walkers and wheelchairs can still be independently mobile but need specially designed environments that are accessible, easy to navigate, and motivate them to leave their beds. As limited research is available on the topic, it is unclear what threshold distance patients using a wheelchair, cane or walker can cover independently.

Ward and Hospital Design Challenges
Architects are faced with a large variety of rules, guidelines, and criteria when designing hospitals, making the design of hospital wards especially challenging [2]. In addition to the different aspects of patient-centered design that are increasingly being considered, such as privacy, control, and family support, many other factors, including infection control, ventilation, fire safety, patient monitoring, patient transport, staff walking distances, staff communication, and foodservice organization, need to be taken into account when designing ward environments. Furthermore, the development of new technologies (e.g., artificial intelligence and robotics, telemedicine, and health wearables) impacts how the designs of hospitals are developed and future-proofed. Therefore, the design of nutrition environments (e.g., communal dining rooms) or mobility-promoting environments might not be one of the main priorities in hospital ward design.
A survey of 119 architects in the United Kingdom revealed that their main priorities for the ward design were view to the outside, nurses' observation, access to sanitary facilities, and infection control [2]. In the same survey, social space was ranked 8th in terms of importance among ten design criteria, without specifying what kind of social space it was. Architects without hospital design experience valued social space less [2]. Staff travel distances were ranked 7th, without mentioning patient travel distances or environments promoting patients' mobility. This study showed that the nutrition and mobility environment design was not mentioned among the top ten priorities for the ward design among the 119 participating architects.
The research on design priorities from other countries is greatly lacking, and healthcare design firms do not readily or openly publish the current design strategies for nutrition and mobility-supporting environments. Nevertheless, architects play a crucial role in creating hospital wards, and their interests can influence and prioritize certain design criteria [2]. At the same time, the care environment, through its architecture and culture, can substantially limit the freedom of both patients and medical personnel to work toward their respective goals [59]. If environments that support the nutritional intake and mobility of patients are not high on the priority list when designing hospitals, this creates an indirect risk for patients, as they will be limited in these aspects during their hospitalization. Therefore, current approaches to designing eating environments in hospitals must be examined in-depth. The same is the case for spatial features supporting the mobility of hospitalized patients.

Future Research Directions
As the connection between nutrition and mobility in the built environment is still under researched, we suggest potential future research directions based on our study results. Multiple factors interplay in the ward environment ( Figure 7); future research could look into the spatial and organizational relationships between the nutrition environment, patients' mobility levels, food types, and the nursing staff. For example, the distance and accessibility to various types of nutrition environments could be examined to determine what distance and dining room organization would enable most patients to be independently mobile. At the same time, the distance of nursing staff to various nutrition environments needs to be examined to establish the best environment type for nurses' supervision, safety concerns, patient transport, and the amount of necessary space to provide meals. This also relates to the nursing staff's involvement in attending meals for patients with different mobility levels. Different food types might require a different type of nutrition environment and a different level of nursing staff involvement.
x FOR PEER REVIEW 13 of 18 toward their respective goals [59]. If environments that support the nutritional intake and mobility of patients are not high on the priority list when designing hospitals, this creates an indirect risk for patients, as they will be limited in these aspects during their hospitalization. Therefore, current approaches to designing eating environments in hospitals must be examined in-depth. The same is the case for spatial features supporting the mobility of hospitalized patients.

Future Research Directions
As the connection between nutrition and mobility in the built environment is still under researched, we suggest potential future research directions based on our study results. Multiple factors interplay in the ward environment ( Figure 7); future research could look into the spatial and organizational relationships between the nutrition environment, patients' mobility levels, food types, and the nursing staff. For example, the distance and accessibility to various types of nutrition environments could be examined to determine what distance and dining room organization would enable most patients to be independently mobile. At the same time, the distance of nursing staff to various nutrition environments needs to be examined to establish the best environment type for nurses' supervision, safety concerns, patient transport, and the amount of necessary space to provide meals. This also relates to the nursing staff's involvement in attending meals for patients with different mobility levels. Different food types might require a different type of nutrition environment and a different level of nursing staff involvement. These proposed connections could be studied both quantitatively and qualitatively. A review of current nutrition environment designs in hospitals worldwide needs to be conducted to establish the existing ward layout organizations. A quantitative research study could compare different layouts with the nutrition environment as a central point, measuring the distance patients need to cover to reach it independently. Barriers to mo- These proposed connections could be studied both quantitatively and qualitatively. A review of current nutrition environment designs in hospitals worldwide needs to be conducted to establish the existing ward layout organizations. A quantitative research study could compare different layouts with the nutrition environment as a central point, measuring the distance patients need to cover to reach it independently. Barriers to mobility can also be mapped on this path by the systematic observation of patients and nurses. The nutritional intake of patients could be measured for each nutrition environment type and the level of nursing staff involvement. Another potentially promising research direction is the association between the covered distance/daily steps and nutritional intake.
As experimental research introducing real-life new nutrition environment concepts is challenging to implement, VR experiments can be conducted instead to explore the spatial needs of patients and nurses. Another possibility would be to test real-size mock-ups, which would require large empty spaces for setting up. At the same time, more qualitative research is needed to explore the experiences of hospitalized patients, especially patients with low mobility levels with the longest lengths of stay. In addition, Nurses' experiences and preferences regarding patients' mobility and independence during mealtimes must be investigated further. We highlight only some options for possible future research into the relationship between the built environment, mobility, and nutrition during hospitalization, as there are many more unexplored topics in this understudied field.
In addition to further examination of how the built environment affects patients' nutritional intake and mobility during hospitalization, personal and organizational factors need to be considered. Even though low mobility has a major impact and can lead to adverse outcomes, patients' understanding of the effects of bed rest may be limited to commonly reported symptoms such as pressure ulcers and chest infections [60]. Patients also believe that food is not a priority during hospitalization and that the hospital environment limits their activity [20]. Therefore, when hospitalized, patients expect to lie in bed most of the time and eat less than usual [20]. Educating patients about the importance of mobility and nutrition is crucial for reducing their functional decline during hospitalization. At the same time, the hospital's organizational culture can greatly influence patients' activity levels and nutritional intake. If patient mobilization is discouraged on the ward (due to safety or other concerns), this creates another limiting factor that the provision of the mobilitysupporting built environment cannot circumvent. Therefore, the nursing staff needs to be educated about supporting the independent mobility of patients during mealtimes, mainly because patient mobilization tends to fade into the background in everyday practice at the hospital [32].

Strengths and Limitations
This study has some potential limitations. Patients with longer lengths of stay in the hospital might be overrepresented due to the cross-sectional research design. The voluntary nature of the survey introduces a selection bias into the study since participating departments are likely to be more interested in nutritional care and adopt more nutritional care interventions. At the level of the patients, a selection based on the severity of the illness cannot be excluded, probably favoring the inclusion of patients in better physical and mental conditions. Another limitation is that food intake measurements were self-reported by patients, which may be less reliable because they are dependent on their individual estimation abilities. Furthermore, the study did not directly examine the impact of various ward design aspects on patients' mobility and food intake.
The major strengths of this research are the use of the same standardized and simple data collection tool in local languages, the large sample size, the multi-national worldwide participation, and the focus on nutritional care factors.

Conclusions
Hospitalization often leads to reduced mobility, reduced food intake, and changes in patients' well-being. These conditions are well known to be associated with poor outcomes. In this study, patients' mobility conditions worsened compared to before hospitalization. Decreased mobility is associated with reduced food intake and decreased well-being. Pa-tients with more reduced mobility and low food intake also stay in the hospital significantly longer. Of the many strategies adopted by the units to improve patient food intake, promoting a positive eating environment was the least frequently observed. The ward structure, seen from an architectural point of view, might be a key factor influencing patients' food intake and mobility. Certain ward designs might promote patients' mobility and nutritional intake, but more studies should be carried out to identify which aspects are more determinant in promoting mobility, food intake, and well-being. Institutional Review Board Statement: The nutritionDay project was approved by the Ethical Committee of the Medical University, Vienna (EK407/2005) and has been amended annually. In accordance with national regulations, the project was also submitted to national or local ethical committees in each participating country. This trial was registered at clinicaltrials.gov as NCT02820246.
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.

Data Availability Statement:
The nutritionDay project provides original data to researchers submitting a protocol that needs to receive approval from the scientific committee and acceptance of the data sharing agreement. All information is available at www.nutritionday.org (accessed on 15 February 2023).